Exam 4 Musculoskeletal pathophysiology

long bones are usually found where

upper and lower extremities

what happens to long bones after puberty

metaphysis and epiphysis fuse tog

what are short bones

irregularly shaped bones in wrists and ankles

examples of flat bones

skull, rib cage, scapula

flat bones purpose

to protect a cavity and vital rogans and to allows for other things to be attached to them

irregular bones example

vertebrae and ethmoid

where is bone marrow found

in medullary cavities of the long bones throughout the skeleton

also found in the cavities of cancellous bone in the vertebrae, ribs, sternum, and flat bones of the pelvis

red vs yellow bone marrow

red for RBC production

yellow made of adipose tissue

spongey bone

cancellous bone. has lots of bone marrow

Bone cells are nourished by diffusion from

canaliculi

Haversian canals

each canal carries 1 – 2 blood vessels, lymphatics, and nerve fibers

Volkmann canals

contain blood vessels; connect adjacent Haversian canals

The distribution of blood in the cortex occurs through the

Haversian and Volkmann canals

what is an important regulator of calcium and phosphate levels in the blood

parathyroid hormone (PTH)

PTH effect on calcium

Prevents drops in calcium levels

PTH regulation

• increased calcium levels inhibits PTH release

  • PTH maintains serum calcium levels by inhibition of calcium release from bone, conservation by the kidneys, enhanced intestinal absorption through activation of Vit. D, and reduction of phosphate levels

    

PTH affect on phosphate

Prevents rises in phosphate levels

relationship of calcium and phosphate

calcium and phosphate have an inverse relationship. as one goes up the other goes down. both controlled by PTH

calcitonin actions

• Inhibits the release of calcium from the bone

  • Causes calcium to sequester in bone cells and inhibit osteoclast activity

• Reduces renal tubular reabsorption of calcium and phosphate

if someone has high calcium, give

calcitonin

Calcitonin synthesis and release is stimulated by

increase in serum calcium

calcitonin clinical uses

Paget disease

Hypercalcemic crisis

Vit. D2:

ergocalciferol

Vit. D3:

cholecalciferol

Why must Vitamin D must be converted?

Must be converted to be physiologically active and metabolized to compounds that mediate its activity

food with high vitamin D

milk, seafood, liver, 

Intestinal absorption of vitamin D occurs mainly in the

jejunum

What can spontaneously convert 7-dehydrocholesterol D₃ to Vit. D₃

UV radiation from sunlight

The most potent Vit. D metabolite is

1,25-dihydroxyvitamin D3 (1,25-(OH)2D3)

1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) actions

• Increases intestinal absorption of calcium and promotes the actions of PTH on resorption of calcium and phosphate from bone

• Intestinal absorption and bone resorption increase the amount of calcium and phosphorus available to the mineralizing surface of the bone

what hormones stimulate 1,25-(OH)₂D₃ production by the kidney

PTH and prolactin

What inhibits 1,25-(OH)2D3 production by the kidney

calcitonin

vitamin d affects

mood, depression, anxiety

Joints

• are sites where 2+ bones meet

ligaments

attach to the joint capsule and bind the ends of bones together

(bone to bone)

tendons

join muscles to the periosteum of articulating bones

(muscle to bone)

dislocation

The displacement or separation of the bone ends of a point with loss of articulation

Subluxation:

partial dislocation

dislocation is often

• result of trauma

• seen in the shoulder and acromioclavicular (AC) joints

dislocation manifestations

• Pain, deformity, limited movement/range of motion (ROM)

fractures occur when

more stress is placed on the bone than it can absorb

fractures categories (NOT classification)

• Sudden injury

  • Most common

• Fatigue or stress

• Pathologic

fractures classification according to

• Classified according to location, type, and direction or pattern of the fracture line

spiral fractures often seen in

domestic abuse or sexual assault

compression fractures often in

vertebrae

manifestations of fractures

• Pain, tenderness at the site

• Inflammation

• Loss of function

  • Loss of nerve function

    • Local shock

• Abnormal mobility

• Deformity

  • Long bones: angulation, shortening, rotation

compartment syndrome

Condition of increased pressure within a limited space that compromises the circulation and function of the tissues

compartnemnt syndrome clinical manifestations

• Severe pain that is out of proportion to the injury

• Paresthesias, diminished reflexes, loss of motor function

compartment syndrome treatment

• Removal of restrictive devices

  • Casts, splints, dressings

• Elevating extremity to reduce edema

• Fasciotomy

  • Incision of the fascia to separate it to allow for compartment to decompress

Those with a lower extremity fracture are at risk for

VTE

fat embolism syndrome (FES)

• life-threatening manifestations resulting from the presence of fat droplets in the small blood vessels of the lung, kidneys, brain after a long bone or pelvic fracture

FES pathogenesis

• Unclear mechanism… thought to result from fat droplets that are released from the marrow or adipose tissue at the fracture site into the venous system through a torn vein

FES manifestations

• Respiratory failure: chest pain, shortness of breath, tachycardia, cyanosis

• Cerebral dysfunction: confusion, change in behaviors, disorientation, seizures

• Skin and mucosal petechiae: chest, axillae, neck, shoulders

FES diagnosis

arterial blood gas

FES treatment

• Correct hypoxemia, inflammation, maintaining fluid balance

Osteopenia

reduction in bone mass greater than expected for age, race, or sex

• occurs due to a decrease in bone formation, inadequate bone mineralization, or excessive bone deossification

major causes of osteopenia

• Osteoporosis

• Osteomalacia

• Malignancy (multiple myeloma)

• Endocrine disorders (hyperparathyroidism, hyperthyroidism)

osteoporosis

• Characterized by a loss of mineralized bone mass causing increased porosity of the skeleton and susceptibility to fractures

  • Often associated with the aging process

osteoporosis Imbalance between bone resorption and formation

Resorption > formation

Some things that my contribute to osteoporisis

• Poor nutrition and decreased physical activity

• Age-related decrease in intestinal absorption of calcium due to deficient activation of Vit. D

Postmenopausal osteoporosis

• Estrogen deficiency… loss of cancellous bone and predisposition to fractures of the vertebrae and distal radius 

Secondary osteoporosis risk factors

• Endocrine disorders: hyperthyroidism, hyperparathyroidism, Cushing syndrome, DM

• Malignancies: multiple myeloma

• Alcohol use disorder

  • Alcohol is a direct inhibitor of osteoblasts and inhibits calcium absorption

• Medication use: corticosteroids (prednisone), aluminum-containing antacids, anticonvulsants

when do people usually recognize they have osteoporosis

The first manifestations of the disease typically accompany a fracture. It is often a silent disorder

clinical manifestations of osteoproriss

• Loss of height 

  • Kyphosis 

• Systemic symptoms (weakness, fatigue, pain) are suggestive that osteoporosis is caused by an underlying disease process

  • more common in Secondary osteoporosis

best way to diagnose osteoporosis

Dual-Energy X-Ray Absorptiometry (DEXA)

osteoporosis treatment

• Regular exercise

• Calcium supplementation

• Vit. D supplementation

• Antiresorptive agents

  • Estrogens and selective estrogen receptor modulators (SERMs)

  • Bisphosphonates

  • Calcitonin

• Anabolic agents

is pain a normal part of the aging process?

pain is NOT part of natural aging process. pain means something is wrong. never write off pain because someone is old 

Osteomalacia and Rickets are characterized by

softening of bone but not loss of bone 

who is affected by Osteomalacia and Rickets

Osteomalacia - adults

Rickets- children

Osteomalacia 2 main causes

• Insufficient calcium absorption from the intestine due to lack of dietary calcium or deficiency of or resistance to the action of Vit. D

• Phosphate deficiency due to increased renal losses or decreased intestinal absorption

Osteomalacia can lead to

chronic renal failure called renal rickets

Osteomalacia clinical manifestations

• Bone pain and tenderness

• Fractures (with disease progression)

• Muscle weakness

  • Severe cases

• Slightly reduced serum calcium levels

what is the best way to treat osteomalacia

• Treat the cause…

  • Nutrition 

  • Sun exposure

rickets etiology

• Kidney failure

• Malabsorptive syndromes (celiac disease, cystic fibrosis)

• Medications (anticonvulsants, aluminum-containing antacids)

• Nutritional rickets

  • Results from inadequate sunlight exposure or inadequate intake of Vit. D, calcium, phosphate

clinical manifestations of rickets

• Bone deformities

  • Unmineralization

  • Enlarged and soft skull

    • Delayed closure of fontanels

  • Deformities are likely to affect the spine, pelvis, and long bones

    • Lumbar lordosis and bowing of the legs

rickets treatment

• Nutrition

  • Diet with calcium, phosphorus, and Vit. D

    • Supplementation 

• Sunlight exposure

Paget Disease progression

• onset - marked by regions of rapidly occurring osteoclastic bone resorption

• later progresses to period of hectic bone formation with increased osteoblasts rapidly depositing bone in a chaotic manner

  • leads to poor quality bones… bowing and fractures

    • Localized to the spine, skull, hips, pelvis

pagat disease etiology

• Genetic and environmental influences

  • big genetic component!! if first degree relative has it your chances go way up

Paget Disease: Clinical Manifestations

often asymptomatic but can have many manifestations

Paget Disease: Clinical Manifestations head

• Headache, intermittent tinnitus, vertigo, eventual hearing loss

Paget Disease: Clinical Manifestations spine

Kyphosis of the thoracic spine

Paget Disease: Clinical Manifestations femur and tibia

• Bowing

• Coxa vara

  • Reduced angle of the femoral neck due to softening

    • Waddling gait

Paget Disease: Clinical Manifestations neurocognitive

• Nerve palsy syndromes

• Mental decline

Paget Disease: Clinical Manifestations cardiovascular

• High-output heart failure

• Calcific aortic stenosis

• Most common cause of death… 

order of pagets disease osteogenic carcinomas

• Femur 🡪 pelvis 🡪 humerus 🡪 tibia

Paget disease diagnosis

• Based upon bone deformity characteristics and XR changes

• Bone scans

• Bone biopsy

paget disease treatment

• • Pain: NSAIDs, anti-inflammatory agents

    • Suppressive agents: bisphosphonates, calcitonin

      • Prevent further spread and neurologic deficits

paresthesia

the sensation of tingling, burning, pricking or prickling, skin-crawling, itching, “pins and needles” or numbness on or just underneath your skin.

should you elevate or lower a limb with compartment syndrome

elevate (reduces edema)

what does vitamin d do

help the body absorb and retain calcium and phosphorus

what kind of fracture is this

impacted

what kind of fracture is this

transverse

what kind of fracture is this

oblique

what kind of fracture is this

spiral

what kind of fracture is this

communited

what kind of fracture is this

segmental

what kind of fracture is this

butterfly

A client with a closed reduction of a wrist fracture has a plaster cast applied. Which nursing intervention is the highest priority immediately after the procedure?

Performing a peripheral circulation assessment

The nurse caring for a child with a deficiency in vitamin D knows that the deficiency places the child at risk for:

rickets

Rheumatoid Arthritis (RA)

Systemic iimmune mediated joint inflammatory disease